Undistorted negative patterns of animal hides



Patented Aug. 19, 1952 UNDISTQRTED NEGATIVE PATTERNS or ANIMAL HIDES Frank Ralph NisseL. Plainfield, N. J., assignor to Union Carbide and. Carbon Corporation, a corporation of New York No Drawing. Application April 13, 1950,

Serial No. 155,787

6= Claims. 1

This invention relates to an improvedprocess of making a negative impression of an animal hide in-a' matrix material. More specifically the invention. contemplates: the impregnation of animal hides with a heat-hardenable resin. and the subsequent hardening of the impregnated hide whereby an undistorted, negative impression thereof may be obtained in the matrix.

By animal hide, as used herein and inthe appended claims, is meant any uncoated animal skin, devoid of hair or fur, whether. or not the same has-been. processed asleather.

Ordinarily, matrices are configurated by pl'acinga pattern material in surface contact. with a matrix blankand applying pressure, and sometimes heat; thereto. Where, however, thepattern material is soft and pliable, the application of pressureacts to disfigurethe relief configuration of the pattern material and results in a. distorted, negative impression thereof in the matrix. An animal hide is one suchsoft pattern material which is particularly difficult-to impress in a matrix'w'ithout surfacepattern distortion. Negative impressions of animal hides, in a matrix composed of a hard material, are extremely valuable as embossing matrices which may be used tosi'mul'ate the surface ofthe-pattern-material on other surfaces. For example, thenormally smooth surface of a tough thermoplastic resin in film or sheet form may be-embossed with such a matrix to give it the appearanceof'various animal-hides, the embossed material beinguseful in thefabrication of shoes,'handbags, brief cases, upholstery and'other articles. v v

The object of this invention is an: improved method of creating a negative impression of an animal hide and consists inmaking s-u'cli hide inflexible by means of impregnation with a heathardenable resin," while leaving unaltered "the surface pattern of the material, thusenabling an undistorted, negative impression to be made in a matrix blank.

The process of the present invention will best be understood by reference to the followingdetailed description of its practice inobtainingundistorted, negative impressionsof various animal hides such as calf, ostrich, snake, and the'l-ike'. I

The hide pattern material is submerged in a uble in either water or alcohol. The. amount of resin. in the impregnating solution may vary considerably. Provided suflicient resin is deposited in thepores of the'skin'to make it hard and rigid when heat is applied, the purpose of the inventionwill be served. Conversely, the resin content must not be so high that the solution viscosity prevents migration into the pores of theskin. In most instances, about one part of resin to three parts of solvent makes a satisfactory impregnating solution which readily migrates into the pores and produces a hard and? inflexible pattern materiat when the resin. ishardened by the applica tion' of heat.

The period of submersion: required tofully impregnate a patternmaterial of animal hide varies withthe pore size of the hide being treated. When the hide is simply'soaked in the resin solutionseveral days may: be required. If the resin solution and hide are placed in a vacuum tank,

the impregnationsperiod may be reduced to a few hours by employing well-known vacuum= impregnation techniques. 7

After the hide is thoroughly impregnated with the resin solution, it is removed therefrom and the skinside is carefully wiped clean of all excess resinas by wiping with a cloth preferably wetted with a solvent for the resin. It is essential that all excess resin clinging to the skin surface of the hide be removed, as anyresin remaining on the surface will result in disfiguration or obliteration of the natural relief pattern of the material. I s

Thereafter, the hide is dried and the resin set-up or hardened by the application of heat. Care must be exercised not toevaporatethe solvent too rapidly during the drying operation;

nor to overheat the resin during the hardening hardened by raising the oven temperature to the normal heat-hardening temperature of the particular resin and holding at this temperature until theresin is fully cured; for instance; one hour at C. is sufii'cient' for a phenol-formaldehyde resin; While the impregnated hideis bein 'drled andthe resin-hardened, it shouldibe-"supported, as by a stretching frame, or mountedona rigid surface to avoid distortion or shrinkage-while hardening into a suitable shape for pressing against a matrixblank." When fully impregnated and hardened the-hide will possess a uniform apfi earanc'e. V

pregnated with the resin solution and the resin impregnated hides must be re-rolledprior to hardening the resin. This is preferably done after the skin has air dried to some extent but while it is still pliable. Generally, air drying from one-half to one hour will place such skins in satisfactory condition for re-rolling. There-- after, they may be placed in a stretching frame and treated in the normal manner.

'Animal hides, impregnated and hardened-according to the hereinabove described process, have a very hard finish and yet have lost none of their original pattern or shape. They may be used, without appreciable damage to their finish, as a pattern material for conventional matrix compositions having sufficient strength to emboss thermoplastic material, as for example, clay, plaster of Paris or metallic alloys melting at a temperature less than 300 C.

A particularly suitable matrix blank for use with the improved process of this invention is that described in U. S. Patent No. 2,278,291 issued to H. Swan et al. However, this matrix blank is composed of a phenolic type resin and therefore has a tendency to adhere to the pattern material when the latter is impregnated with the same type resin and pressed thereagainst at the elevated temperature required to harden the phenolic matric material. This sticking may be avoided without any appreciable effeet onthe pattern transferred to the matrix by applying to the surface of the pattern material a thin coat of a colloidal suspension of graphite in water. This coating should be re-applied prior to pressing each second or third matrix. As many as 50' phenolic matrices have been made in this manner from a single hide treated as herein described with no appreciable loss in detail of pattern material.

In pressing matrices in the manner outlined above, it is preferable to support the pattern material on a metal or other hard surface to which it may be secured by a phenolic binder or With such, skins, the rolled finish is lost when they are im-,

other suitable adhesive capable of withstanding I the pressing temperature used in forming the matrix (about 180 C. with the phenolic type matrix blank) What is claimed is:

1.'In theprocess of making a negative im- ,partingrigidity and hardness to said hide, cleaning the surface of said hide of any excess impregnant, hardening said resin by the applicatio Of heatthereto to cause said hide to'become hard and inflexible, and thereafter impressing said matrix with the resin-hardened hide.

2. The process of making a negative impression of ananimal hide which comprises impregnating said hide with a heat-hardenable resin capable of imparting rigidity and hardness to saidhide, removing any excess of. impregnant from the surface of said hide, hardening said resin by the application of heat to cause said hide to become hard and inflexible, and pressing said resin-im 4 pregnated hide against a matrix blank with sufficient pressure to form said impression therein.

3. 'In the-process of yembossing/on thermoplastic-materialthe relief patten of an animal hide, by pressing said hide against a matrix blank to form a negative impression of said hide in said matrix blank, and thereafter embossing said thermoplastic material by means of the matrix so formed, the improvement which comprises. impregnating" said animal hide with a solution of a heat-hardenable resin capable of imparting rigidity and hardness to said hide, removing any excess impregnant from the surface of the hide, extracting the solvent from the impregnating resin at a rate insuflicient to cause bubble formation in the resin, and thereafter hardening said resin with heat to produce a hard and inflexible pattern material of said animal hide.

4. In the process of making a matrix, composed of a heat-hardenable phenolicresin, by embossing therein the negative impression of an animal hide, the improvement which comprises impregnating said pattern material with a heat-hardenable phenolic resin capable. of imparting rigidity and hardness to said hide, removing any excess impregnant from the surface of said hide, hardening the resin in said hide by the application of heat thereto to thereby convertsaid animal hide into a hard and inflexible material, coating said resin-hardened hide with a thin layer of a colloidal suspension of graphite in water, and thereafterconfigurating the matrix blank with a negative impression of said hide by pressing the two together.

5. The process of making a negative impression of the surfaceconfiguration of an animal hide with a rolled finish, which process comprises impregnating said hide with a solution of a heathardenable resin capable of imparting rigidity and hardness to said hide, cleaning any excess impregnant fromthe surface of said hide, extracting the solvent from the impregnated hide until its pliability approximates that of its preimpregnated condition, re-rolling the impregnated hide until the rolled finish is reproduced, removing the remainder of they solvent, hardening the impregnating resin by the application of heat to cause said hide to become hard and inflexible, and pressing said resin-impregnated hide against a matrix blank with'sufiicient pressure to form said negative impression in said matrix blank.; I 1 i 6. A process of treating an animal, hide which comprises impregnating a hide with a solution of aheat-hardenable resin' capable of rendering said hide hard and inflexible, thereafter removing resin remaining on the skin surface of said hide from the impregnation step to thereby retain the natural relief pattern of the hide, and then drying and hardening the resin in the ,impregnated hide while the'hideis supported to prevent distortion and shrinkage thereof during the hardening ofthe resin. FRANK RALPH NISSEL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,930,158 Chandler Oct. .10, 1933 2,255,335 Schroeder, Sept. 9, 1941 

1. IN THE PROCESS OF MAKING A NEGATIVE IMPRESSION IN A MATRIX BLANK BY MEANS OF A PATTERN MATERIAL COMPOSED OF AN ANIMAL HIDE, THE IMPROVEMENT WHICH COMPRISES IMPREGNATING SAID HIDE WITH A HEAT-HARDENABLE RESIN CAPABLE OF IMPARTING RIGIDITY AND HARDNESS TO SAID HIDE, CLEANING THE SURFACE OF SAID HIDE OF ANY EXCESS IMPREGNANT, HARDENING SAID RESIN BY THE APPLICATION OF HEAT THERETO TO CAUSE SAID HIDE TO BECOME HARD AND INFLEXIBLE, AND THEREAFTER IMPRESSING SAID MATRIX WITH THE RESIN-HARDENED HIDE. 